cmd/mecha: add ability to compile Zig modules to mecha build command

Signed-off-by: deadprogram <ron@hybridgroup.com>

cmd/mecha/README.md

@@ -50,33 +50,33 @@ GLOBAL OPTIONS:
    --version, -v  print the version
 ```
 
-## New project
+### New project
 
 ```bash
 mecha new project example.com/myproject
 ```
 
-## New project based on template
+### New project based on template
 
 ```bash
 mecha new project -t=blink example.com/myproject
 ```
 
-## New module
+### New module
 
 ```bash
 mecha new module mymodule
 
 ```
 
-## New module based on template
+### New module based on template
 
 ```bash
 mecha new module -t=blink mymodule
 
 ```
 
-## Build modules in current project
+### Build modules in current project
 
 ```bash
 mecha build
@@ -88,8 +88,27 @@ or
 mecha build modules
 ```
 
-## Build application for current project
+### Build application for current project
 
 ```bash
 mecha build project
 ```
+
+## Using `mecha` with Rust
+
+If you want to use the `mecha` command with Rust, you will need to install Rust as follows.
+
+- First install Rust by using the instructions here: https://www.rust-lang.org/tools/install
+
+- Then, install the Rust `wasm32-unknown-unknown` target.
+
+```bash
+rustup target add wasm32-unknown-unknown
+```
+Any Rust modules in your project's `modules` directory should be automatically built when you run the `mecha build` command.
+
+## Using `mecha` with Zig
+
+If you want to use the `mecha` command with Zig, you will need to install Zig 0.11.0 by using the instructions here: https://ziglang.org/learn/getting-started/#installing-zig
+
+Any Zig modules in your project's `modules` directory should be automatically built when you run the `mecha build` command.

cmd/mecha/build.go

@@ -111,6 +111,15 @@ func buildModules(cCtx *cli.Context) error {
 				continue
 			}
 
+			// check if there is a build.zig file in the directory
+			_, err = os.Stat(filepath.Join(wd, "modules", f.Name(), "build.zig"))
+			if err == nil {
+				if err := buildZigModule(filepath.Join(wd, "modules"), f.Name()); err != nil {
+					return err
+				}
+				continue
+			}
+
 			// no go.mod or Cargo.toml file found
 			fmt.Println("No module files found in", f.Name(), "skipping...")
 		}
@@ -176,6 +185,37 @@ func buildRustModule(modulesPath, name string) error {
 	return nil
 }
 
+func buildZigModule(modulesPath, name string) error {
+	s := spinner.New(spinner.CharSets[5], 100*time.Millisecond, spinner.WithWriter(os.Stdout))
+	s.Suffix = " Building Zig module " + name
+	s.FinalMSG = "Done.\n"
+	s.Start()
+	defer s.Stop()
+
+	fmt.Println("Building Zig module", name)
+	modulePath := filepath.Join(modulesPath, name)
+	os.Chdir(modulePath)
+	defer os.Chdir("../..")
+
+	cmd := exec.Command("zig", "build")
+
+	var stdoutBuf, stderrBuf bytes.Buffer
+	cmd.Stdout = io.MultiWriter(&spinWriter{s, os.Stdout, false}, &stdoutBuf)
+	cmd.Stderr = io.MultiWriter(&spinWriter{s, os.Stderr, false}, &stderrBuf)
+
+	if err := cmd.Run(); err != nil {
+		fmt.Printf("zig build error %s: %v\n", modulePath, err)
+		os.Exit(1)
+	}
+
+	if err := copyFile(filepath.Join(modulePath, "zig-out", "lib", name+".wasm"), filepath.Join(modulesPath, name+".wasm")); err != nil {
+		fmt.Printf("copy file error %s: %v\n", modulePath, err)
+		os.Exit(1)
+	}
+
+	return nil
+}
+
 // copyFile copies the given file or directory from src to dst. It can copy over
 // a possibly already existing file (but not directory) at the destination.
 func copyFile(src, dst string) error {